The use of sputtering in order to deposit coatings on substrates is known in the art. For example, and without limitation, see U.S. Pat. Nos. 5,922,176; 5,403,458; 5,317,006; 5,527,439; 5,591,314; 5,262,032; and 5,284,564, the entire contents of each of which are hereby incorporated herein by reference. Briefly, sputter coating is a thin film coating process that involves the transport of almost any material from a target to a substrate of almost any other material. The ejection of the target material is accomplished by bombarding the surface of the target with gas ions accelerated by a high voltage. Particles are ejected from the target as a result of momentum transfer between the accelerated gas ions and the target. Upon ejection, the target particles traverse the sputtering chamber and are subsequently deposited on a substrate as a thin film.
Sputtering processes typically utilize an enclosed chamber confining a sputtering gas, a target electrically connected to a cathode, a substrate, and a chamber which itself may serve as the electrical anode. A power supply typically is connected such that the negative terminal of the power supply is connected to the cathode and the positive terminal is connected to the chamber walls. In operation, a sputtering gas plasma is formed and maintained within the chamber near the surface of the sputtering target. By electrically connecting the target to the cathode of the sputtering power supply and creating a negative surface charge on the target, electrons are emitted from the target. These electrons collide with atoms of the sputtering gas, thereby stripping away electrons from the gas molecules and creating positively charged ions. The resulting collection of positively charged ions together with electrons and neutral atoms is referred to generally as a sputtering gas plasma. The positively charged ions are accelerated toward the target material by the electrical potential between the sputtering gas plasma and the target and bombard the surface of the target material. As ions bombard the target, molecules of target material are ejected from the target surface and coat the substrate.
One known technique for enhancing conventional sputtering processes involves arranging magnets behind or near the target to influence the path taken by electrons within the sputtering chamber, thereby increasing the frequency of collisions with sputtering gas atoms or molecules. Additional collisions create additional ions, thus further sustaining the sputtering gas plasma. An apparatus utilizing this enhanced form of sputtering by means of strategically located magnets generally is referred to as a magnetron system.
Conventional sputtering apparatuses work well when depositing one or two thin film layers, as some single-chamber designs are configured to deposit the same. Unfortunately, however, conventional sputtering techniques suffer from several disadvantages. As layer stacks become more complex, e.g., at least in requiring multiple layers in a single layer stack, conventional sputtering apparatuses encounter difficulties. For example, one must typically determine how best to use one's existing equipment in depositing more complicated layer stacks, or at least layer stacks with more layers.
One possible solution to such difficulties involves providing additional sputtering chambers. Separate sputtering apparatuses may even be supplied. However, as more chambers are added to a single sputtering apparatus, or as more individual sputtering apparatuses are added to a fabrication facility, additional space is required. In addition to requiring more space, which in some instances may be at a premium, the equipment costs also can be prohibitively high, particularly when the added equipment may not be necessary for all layer stacks being produced at a given facility.
Another possible solution to such difficulties involves temporarily halting the assembly line, removing a target in a sputtering chamber, and restarting the assembly line. However, this solution may require the sputtering chamber to be vented (e.g., in the event that an inert gas is being used in connection therewith), cooled (e.g., as sputtering typically takes place at several hundred degrees Celsius), pressurized (e.g., as sputtering typically is performed in an at least partial vacuum), etc. Because these wait times are imposed, yield is reduced, as people and intermediate products are simply “waiting around” during these configuration and reconfiguration processes. Production speeds may be significantly decreased because of the waiting involved in such processes.
The above and/or other problems may be exacerbated when a plurality of different materials to be deposited using different kinds of targets are requirement. For example, it may not always be possible to switch from a planar target of a first material to a cylindrical target of a second material, or even a cylindrical target of the same first material. Needless to say, it may become even more difficult to selectively incorporate an ion beam in such sputtering apparatuses.
Thus, it will be appreciated that there is a need in the art for improved sputtering apparatuses and/or methods. For example, it will be appreciated that there is a need in the art for improved sputtering apparatuses that are selectively reconfigurable and/or methods associated with the same.
In certain example embodiments of this invention, a sputtering apparatus for sputter coating an article in a reactive environment is provided. The sputtering apparatus includes a vacuum chamber. A cathode has a hollow body portion. A substantially planar yoke is provided between the cathode and chamber, with the yoke including at least first and second target locations provided on a first major surface thereof, and at least third and fourth target locations provided on a second major surface thereof. The at least first and second target locations at least initially face the vacuum chamber, and the at least third and fourth target locations at least initially face the cathode. The yoke is rotatable such that, upon a rotation, the at least third and fourth target locations face the vacuum chamber and the at least first and second target locations face the cathode. Upon a further rotation, the at least first and second target locations face the vacuum chamber, and the at least third and fourth target locations face the cathode.
In certain example embodiments of this invention, a sputtering apparatus for sputter coating an article in a reactive environment is provided. At least one power source is provided. A vacuum chamber is provided. A cathode has a hollow body portion. A yoke is provided between the cathode and chamber, with the yoke including at least one target location provided on each major surface thereof. A plurality of sputtering targets is provided, with each sputtering target being provided to one of the target locations. Each sputtering target provided on the major surface of the yoke closest the vacuum chamber protrudes into the vacuum chamber, while any other sputtering target(s) is/are recessed in the body portion of the cathode. The yoke is rotatable about an axis such that a rotation thereof causes at least one different sputtering target to protrude into the vacuum chamber. Only the sputtering target(s) protruding into the vacuum chamber receive power from the at least on power source.
In certain example embodiments of this invention, a method of sputter coating a plurality of articles is provided. A sputtering apparatus is provided, with the sputtering apparatus comprising: at least one power source; a vacuum chamber; a cathode having a hollow body portion; and a yoke provided between the cathode and chamber, the yoke including at least one target location provided on each major surface thereof; and a plurality of sputtering targets, each said sputtering target being provided to one said target location. Each sputtering target provided on the major surface of the yoke closest the vacuum chamber protrudes into the vacuum chamber, while any other sputtering target(s) is/are recessed in the body portion of the cathode. The yoke is rotatable about an axis such that a rotation thereof causes at least one different sputtering target to protrude into the vacuum chamber. Only the sputtering target(s) protruding into the vacuum chamber receive power from the at least on power source. At least one said target location is configured to accommodate an ion beam source in place of a sputtering target. A first article is provided to the sputtering apparatus. A first thin film is sputter deposited, directly or indirectly, on the first article. The yoke is rotated. A second article is provided to the sputtering apparatus. A second thin film is sputter deposited, directly or indirectly, on the first article, with the second thin film being different from the first thin film at least in terms of composition.
In certain example embodiments of this invention, a sputtering apparatus for sputter coating an article in a reactive environment is provided. The sputtering apparatus comprises at least one power source, a vacuum chamber; and a cathode having a hollow body portion. A plurality of yokes are provided between the cathode and chamber, with each said yoke including at least one target location provided on each major surface thereof. A plurality of sputtering targets are provided, with each said sputtering target being provided to one said target location. Each sputtering target provided on the major surfaces of the yokes closest the vacuum chamber protrudes into the vacuum chamber, while any other sputtering target(s) is/are recessed in the body portion of the cathode. The yokes are rotatable about an axis such that a rotation thereof causes at least one different sputtering target to protrude into the vacuum chamber. Only the sputtering target(s) protruding into the vacuum chamber receive power from the at least on power source. According to certain example embodiments, the yokes may be individually rotatable.
The features, aspects, advantages, and example embodiments described herein may be combined to realize yet further embodiments.